Friday, June 21, 2002

Hair of the dog

I see that New Jersey will be passing out potassium iodide pills as a precaution against various types of radiological terror.

The devil in me makes me point out that these pills will be radioactive.

Why? The potassium. About a percent or so of all potassium is a radioactive isotope. Sic a Geiger counter on some salt substitute (potassium chloride) and you'll see what I mean (you have a Geiger counter laying around, don't you?)

Of course potassium is essential to your body, particularly for your heart. So if your body can't handle some radiation, it's a pretty bad design, eh?

UPDATE: The percentage of radioactive potassium found in naturally occurring potassium is significantly smaller than "a percent or so" as mentioned above. According to this PDF it's about .012%. The idea is the same though.

There's other interesting stuff in that PDF, such as this:
Hence, the potassium-40 content in the body is constant, with an adult male having about 0.1 microcurie (┬ÁCi). Each year, this isotope delivers doses of about 18 millirem (mrem) to the soft tissues of the body and 14 mrem to bone.
That's just from living, folks - if you're a human being you have no practical way to avoid it. Keep those numbers in mind the next time someone wants to spread radiological terror.

No comments: